Lead-in wire puller device



y 1941. s. A. PLATT LEAD-IN WIRE FULLER DEVICE 2 Sheets- Sheet 1 Filed June 25, 1940 INVENTOR ftp/7021f. PM 724,...

ATTORIGEY May 6, 1941. s. A. PLATT LEAD-IN WIRE FULLER DEVICE Filed June 25, 1940 2 Sheets-Sheet 2 1 5 6 1 6: a" @448 O 6% 74 4 If (7 l 7 a." 17/ g! 4 V mg v v l\ J I "l T a i i a qi l'--- G I ENTOR .S'fep/I [LP/a2? Patented May 6, 1941 LEAD-1N WIRE PULLER DEVICE Stephen A. Platt, Nutley, N. J., assignor to Wilbur B. Driver Company, Newark, N.J., a corporation of New Jersey Application June 25, 1940, Serial No. 342,317

9 Claims.

This invention relates to lead-in wire puller devices for use in the forming of lead-in wire extensions on coils comprised of wire, particularly coils comprised of electrical resistance wire,

such as wire comprised of chromium-iron, chromium-nickel-iron and chromium-nickelalloys.

Heretofore in the art it has been customary to wind a length of wire helically into a coil of a length greater than the desired final length and' thereafter to straighten out the coil convolutions at opposite ends to obtain a coil of the desired final length and to form lead-in wire extensions of the said coil. Annealed electrical a resistance wires of the compositions used generally in the art are relatively soft and ductile and are very easily scratched or marred superficially or deformed cross-sectionally during this straightening operation thereby materially altering the current carrying capacity of the leadin length of wire with resultant deleterious efiect on'the ultimate life of the electrical resistance coil or unit incorporating the coil.

One of the objects of the presentinvention is to provide a lead-in wire puller device that will I In accordance with these objects I have discovered that by securing the end of the wire forming the last coil turn and then unrolling the end convolutions about a rotating spindle in a direction substantially normal to the coil axis,

the unrolled length of wire thereby obtained is substantially free from surfacescratches, mars or indentations and cross-sectionally undeiormed, and I have further discovered that by unrolling the end convolutions in a direction substantially normal to the coil axis but along an arcuate path opposing the arcuate bend of the unrolling convolutions the resultant unrolled length of wire can be obtained substantially straight.

Before further disclosing the present inven- 'tion, reference should be made to the accompanying drawings illustrating one specific embodiment of the lead-in wire puller means of the present invention:

In the drawings:

Fig. 1 is a top view of the lead-wire puller device of the present invention;

Fig. 2 is a partial front elevatio'nal view of the same;

Fig. 3 is a partial side elevational view of the same;

Fig. 4 is an enlarged top view illustrating the uncoiling operation of the device;

Fig. 5 is a full side elevational view;

Fig. 6 is a section along plane 6--6 of Fig. 3;

Fig. 7 is an enlarged sectional View shown in perspective to illustrate one operating position of the device;

Fig, 8 is an enlarged side View of the same; and

Fig. 9 is a second enlarged view of the same illustrating a second operating position.

Referring to the drawings, the unrolling means of the present invention comprises essentially a means A adapted to securely grip the wire end of the last coil turn of the coil, a rotating spindle means B adapted to be axially disposed manually within the coil and having a length suflicient to engage a plurality of coil turns, a curved path C along which the coil turns may be unrolled and an adjustable stop means D on the curved path limiting the extent of coil unrolling.

The device as illustrated requires manual coordination between means A, C, D and means B inasmuch as such manual coordination by all operator has proven more economically practical in the uncoiling of coils of different coil and wire diameters. However, mechanical coordination and automatic cooperation between means A, B, C and D under any standardized conditions of coil diameter and wire size may be readily effected as one skilled in the art may perceive.

In operation, the coil E is placed in a position locating the ends (e) of the last coil turn under means A which is then downwardly actuated to grippingly engage the said end (6). R0- tating spindle means B then is inserted within the open end of the coil E and retained in substantially axial alignment with the coil axis by one hand of the operator and the coil E adjacent the coil end is then engaged by the other hand of the operator. The coil E and rotating spindle means B then are simultaneously moved downwardly along the curved paths C in a direction maintaining the unrolling length of wire substantially normal to the coil axis until stop means D interrupts the motion. Means A is then released, means B is returned to rest position indicated in Fig. 1 and the aforementioned cycle of operations is repeated on the opposite coil end, if desired, or on a second coil E.

As illustrated in Fig. 5, means A is a foot actuated clamping means operating against spring tension means I tending to maintain the moving jaw 2 of means A in open position. This arrangement appears most simple for practical purposes as the moving jaw I then maybe secured on the end of slide lever arm 3 slidably mounted in frame F secured to table top T to be verticall; movable downwardly into engaging position by foot lever 5 pivotally supported at 4 and upwardly to a disengaging position by spring tension means I opposing the downward movement of means 5. Any convenient stop means may be employed to limitthe extent of movement imparted by either means I and 5. The specific stop means illustrated comprises a grooved recess 6 in the lever 3 having a width greater than strap 1 horizontally sustained on frame F in the recess 6, the difference between the recess and strap width representing the extent of vertical movement of lever 3 in either direction. 7

To facilitate the locating of coil E in a position to be engaged by means A, I provide a die seat 8 horizontally mounted on frame F on which coil E is located and a horizontally adjustable guide plate 9 to adapt the device for use with different coil sizes or diameters within the range utilizable with any given sized moving jaw I. Jaw I also may be made removable or replaceable substantially as indicated to permit the use and adaptation of the device to different ranges of coil diameters or wire sizes, as one skilled in the art may perceive.

Means C is preferably an arcuate strip or strap of material such as iron or steel of relative smooth surfaced characterictics and is mounted substantially as shown to form a substantially downwardly curved continuation of die block 8. The strip or strap C preferably is of sufiicient strength and rigidity ,to be substantially nonyielding, to obtain which the free end of the strip or strap C may be secured if desired. A plurality of means C may be provided, each with a different curvature to adapt the device for use in ,the uncoiling of coils E of difierent diameters or of different physical characteristics.

' Rotating spindle means B comprises a flexible shaft lI rotatably driven by an electric motor means (not shown) provided with a rheostat means (not shown) to vary the rate or speed of rotation. This particular means of rotatably driving flexible shaft II is old per se and forms no part of the present invention except in combination with the remaining elements of the invention. A ball bearing hand piece I2 encloses the end of flexible shaft II and a chuck means I3 is secured onto the end of shaft II for engaging the spindle B. By theuse of chuck means I3 different sized spindles B may be employed as the occasion demands.

Ingeneralgl have found that the speed of rotation of spindle B may be varied widely without essential departure from the present invention. Hereto fore in the art, many types of rotatable. spindles as contrasted to power driven rotating spindles'have been proposed for lead pullers. The small friction area of wire contacting the rotatable spindle is insufficient to overcome the internalfriction of the spindle amplified by the side pressure exerted during the pul1- ing of the wire. By power driving the spindle to rotate the same preferably in the direction of coil unwinding and providing a highly polished and hardened surface on the spindle the frictional contact between the wire surface and spindle surface is substantially eliminated and the unrolling of the coil turns thereby is greatly facilitated. In general, electrical resistance wire is relatively soft in the annealed and coiled condition and relatively low power is required to effect the uncoiling of the lead end. A power representative of a speed of rotation approximating 500 R. P. M. appears suflicient for most purposes where the shaft I I is driven by a & horsepower motor. Where the coils E are formed of relatively stiff material the increased pressure required to unroll the coil will require an increased power in the motor means employed to drive shaft II. In general, the slower the rate of coil unwinding the slower the rate of rotation of spindle B, and the stiffer the wire and the greater the pressure required to unroll the coil turns thegreater the power required with any given rate of revolution of spindle B. However, under any given conditions the actual rate of rotation of spindle B may be widely varied without essential departure from the present invention, as one skilled in' the art will readily perceive.

From ,the above description and drawings; illustnating the specific embodiment of the apparatus invention of the present invention, it is believed apparent that the same may be widely varied without essential departure therefrom' and all. such are contemplated as may fall within'the scope of the following claims.

What I claim is:

1. The method of unrolling a plurality of coil turns adjacent the end of a coiled length of wire to obtain an uncoiled .length of wire suitable for use as a lead-in wire for the said coil, which comprises securing the wire end of the last coil turn, inserting a rotating spindle within the coil end, and pulling the coil and spindle in a direction away from the secured endand in a direction substantially normal to the axes of the coil and spindle.

'2. The method of unrolling a plurality of coil turns adjacent the end of a coiled length of wire to obtain a substantially straight uncoiled'length of wire substantially free from surface scratches, indentations and deformations, which comprises securing the wire end of the last coil turn, inserting a rotating spindle within the coil and pulling the coil and spindle in a direction away frorn the secured end substantially normal to: the

axis of the coil and spindle and along a curved path having a curvature reverse to the curvature of the coil at least sufficient to impart a reverse bend to the uncoiled length of wire operative to straighten out the same.

3. In a lead wire puller device, the combination of means to horizontally locate a coil with the end of the last coil turn secured, a runway extendingsaway from the secured coil end in a direction substantially normal to the coil axis ture opposite to the curvature of the unrolling coil turns.

5. The device of claim 3, said last mentioned means comprising a rotating spindle having a diameter smaller than the coil diameter, a length approximating a plurality of coil turns, and a substantially smooth hardened surface.

6. The device of claim 3, said last mentioned means comprising a power driven rotating spindle, the diameter of the spindle being less than that of the inside diameter of the coil and the length thereof at least approximating that of a plurality of coil turns, and having a substantially smooth hardened surface, the power driving said spindle being at least sufficient to maintain rotation of the spindle in opposition to the frictional engagement thereof with the inner coil surface incident to the joint movement of the said coil along said runway.

'7. A lead-in wire puller device for coils comprised of metal wire, said device comprising in combination a horizontally located seat upon which to dispose said coil, means-at one end of said seat to secure the end of the wire forming the last coil turn, a runway extending outwardly from said seat in a direction substantially normal to the coil axis, an adjustable stop means limiting the length of said runway, and means to move the coil along said runway with a simultaneous unrolling of the coil turns adjacent the secured end.

-8. The device of claim 7, wherein said last mentioned means comprises a power driven r0- tating spindle having a diameter less than the inside diameter of the said coil, a length approximating a plurality of coil turns, and a substantially smooth hardened surface.

9. The device of claim 7, wherein said runway is provided with a curvature opposite to that of the unrolling coil turns at least sufficient to impart a reverse bend to the unrolled length of wire.

STEPHEN A. PLATT. 

